The invention relates to a range of low voltage circuit breakers with double housing and one or more poles, made up from standard single-pole breaking units housed in a common molded case and in which each single-pole unit comprises a parallelepipedic insulating box having two opposite parallel large side faces and two opposite parallel small side faces and containing a movable contact, pivotally mounted on an axis perpendicular to said large faces, and designed to cooperate with a stationary contact, adjacent to a small face which bears a terminal connected to the associated stationary contact, several single-pole units being arranged in parallel in the case of a multipole circuit breaker.
Depending on the type of electrical installation, protective circuit breakers are either single-pole or multipole, for example with two, three or four poles. For a given rating, the manufacturer offers a range of molded case circuit breakers. Some components or parts of these circuit breakers, notably the contact parts and extinguishing chambers, are common to the different poles. However this standardization, indispensable to reduce the manufacturing cost, is not taken very far. In modular systems, well-known to those specialized in the art, multipole circuit breakers are achieved by assembly of single-pole circuit breakers, but these systems do not take account of the possibility of using certain parts, notably the operating mechanism, for actuation of all the circuit breaker poles. It is moreover difficult to achieve sufficiently solid and aesthetic assemblies between single-pole circuit breakers.
It has already been proposed to achieve circuit breakers by assembly of single-pole units, housed in cases of different sizes, to accommodate either one or several poles in the case of a multipole circuit breaker.
These circuit breakers do not respect modularity, in the sense that the width of a multipole circuit breaker is not a multiple of that of the single-pole circuit breaker. The pitch between the terminals is also different between a multipole circuit breaker and single-pole circuit breakers adjoined to one another. This pitch difference prevents a power supply by distribution bars, provided with regularly spaced feeders.